This invention relates to a ribbon feed system of a combined printer capable of printing characters both by using types and by using a series of wires in a row for forming characters in a matrix of dots by feeding a print ribbon intermittently a predetermined distance each time one character is printed or by feeding same continuously depending on the type of printing selected to be performed.
Generally, when printing is performed by using types, it is possible to print characters, symbols, etc., clearly is a well-defined manner. However, limitations are placed on the number of types available for printing characters and symbols and it takes time for a control unit of a printer to select a designated type, making it impossible to increase the speed at which printing is effected beyond a certain limit. When characters are printed by forming a matrix of dots by using a dot printer, a print head is moved at a predetermined speed while wires are selectively actuated in accordance with pattern data. Thus, this type of printer offers the advantage that no limitations are placed on the number of characters to be printed and printing can be performed at high speed. However, the disadvantage associated with this type of printer is that the use of a combination of dots for forming characters makes it difficult to print characters in a clear and well-defined form.
To obviate the aforesaid disadvantage of the prior art, proposals have been made to use a combined printer comprising a first printing section and a second printing section which are moved along a line in which characters are being printed so as to perform the printing of characters both by using types and by using a series of wires in a row. In the combined printer of the prior art, it has been the usual practice to switch the printer between two ribbon feeding modes each time the first printing section or second printing section is selected, so that the print ribbon can be moved a predetermined distance each time one character is printed when the first printing section is selected and the print ribbon can be continuously moved when the second printing section is selected.
The combined printer of the prior art which is switched between the two ribbon feeding modes has suffered the disadvantage that its operativity is low because of the need to switch the printer between the two ribbon feeding modes each time one of the two printing sections is selected.